Transmission



" June 2, 9 2. c. L. BIXBY TRANSMISSION Filed May 6, 1940 2 Sheets-Sheet1 WW Z 5 r m x 2 7/4WZ June 2, 1942. c. L. BIXBY 2,285,142

TRANSMISS ION Filed May 6, 1940 2 Sheets-Sheet 2 23752627232".- 64% L.fiz'xgy Patented June 2, 1942 TRANSMISSION Carl L. Bixby, BerrienSprings, Mich., assignor to Clark Equipment Company, Buchanan, Mich,

a corporation of Michigan Application May 6, 1940, Serial No. 333,50?!

8 Claims.

This invention relates to transmissions, and more particularly isdirected to transmissions of the type used in trucks, busses and similarvehicles in which four or more speeds forward are provided, although notlimited thereto.

One of the difficulties of a transmission of this a type resides in theinability to properly lubricate certain of the gears which are disposedintermediate other gears and are thereby isolated to some'extent fromthe normal lubricating paths of the transmission arrangement. This isparticularly true in the case of second speed gears which are confinedagainst axial movement on the main shaft of the transmission but arerotatably journalled thereon intermediate the first and third speedgears.

The present invention has for one of its primary objects the provisionof a gear structure so designed that it is capable of transmittinglubricant thrown laterally against the face thereof radially inwardlytoward the center of the gear against centrifugal force to the rollerbearings upon which the gear is mounted.

I accomplish this object by providing thegear with diagonally extendingpassagewaysleading from the hub portion thereof radially and axiallyoutwardly to suitable boss portions formed on the lateral side face ofthe gear. The openings for these passageways are disposed in the bossportions in such position as to scoop up lubricant thrown off from thepoint of meshing engagement of adjacent change speed gears in thetransmission. 7

It is apparent to those skilled in the art that in a transmissionconstruction, lubricant on the gear teeth is thrown off laterally fromthe point of meshing engagement at a considerable velocity. The presentinvention makes use of this condition by disposing the gear to belubricated in such manner that the passageways therein during rotationof this gear pass through the lateral discharge of lubricant with theouter ends of the passageways being so shaped as to receive thisdischarge and conduct it radially and axially inwardly to the bearingsupon which the gear is mounted. The passageways are angled slightly withrespect to true radii of the gear, and are also angled with respect to amedian radial plane through the gear. As a result the centrifugal forcebuilt up by rotation of the gear is insufficient to counteract thevelocity of the oil or other lubricant that is forced into the open endof the passageways, and this oil is conducted inwardly to the bearings.V

' Obviously, it is not desirable to supply the roller bearings uponwhich a, gear is mounted with too much lubricant, as this causesoverheating of the bearings and also rapid destruction of thecharacteristics of the lubricating oil. By the present invention, I findthat sufficient lubrication is produced in the rotatably mounted gear,but that over-lubrication is prevented, and, as a consequence, a cool,smooth running gear mounting is provided which is adequately lubricated.

Other objects and advantages of the present' invention will appear morefully from the following detailed description which, taken inconjunction with the accompanyingdrawings, will disclose to thoseskilled in the art the particular construction and operation of thepresent invention.

In the drawings:

Figure 1 is a transverse sectionalview through a transmission embodyingthe present invention; and

Figure 2 is a side elevational View of the gear with cooperatingportions of the transmission shown diagrammatically.

Referring now in detail to the drawings, a transmission is indicatedgenerally at 5 comprising the clutch shaft 6 having the recessed end Iin which is piloted the stub end 8 of a transmission main shaft,indicated generally at 9, which, at its opposite end, is carried inbearings l0 secured in the rear end wall l2 of the transmission housing.The clutch shaft 1 is provided with the conventional external gear teeth13 meshingwith the teeth on the gear l4 keyed or otherwise secured to acountershaft [5. The portion N5 of the transmission main shaft issplined to receive the clutch sleeve I! which, together with thesynchronizer sleeve l8, provides means for directly clutching the shaft6 to the shaft 9 in the manner described in detail in the copendingapplication of Leo A. Bixby and Robert Lapsley, Serial No. 298,391,filed October T. 1939.

A second gear 20 is rotatably mounted by bearings 22 upon the portion 23of the shaft- 9, and is adapted to be clutched to the shaft 9 throughthe. synchronizer mechanism described in detail in the aforesaidcopending application. The gear 20 is provided with the external gearteeth 24 which are in constant meshing engagement with the teeth 25 ofthe gear 25 keyed as at 2'! to the countershaft i5. Inasmuch as both ofthe gears 20 and 26 are secured on their respective shafts that they arerotated at all times that power is being introduced into thetransmission through the clutch shaft 6, since the shaft 6 and thecountershaft l4 are in constant meshing engagement.

The countershaft is provided axially rearwardly of the gear 26 with anintegrally formed gear portion 28 having gear teeth 29 meshing with theteeth 30 of a second speed gear 32, which gear is provided With the hubportion 33 mounted as by means of roller bearings 34 upon the portion 35of the shaft 9. The gear 32 is locked against axial movement by means ofthe thrust washers 36 and 31 at opposite ends thereof, the washer 31being secured in position against the enlarged splined portion 38 of thetransmission main shaft which carries the axially shiftable first speedgear 39 having external teeth 40 adapted to be shifted axiallyrearwardly from the position shown in Figure 1 into meshing engagementwith the gear teeth 42 carried by the countershaft.

The hub portion 33 of the gear 30 is provided with the axial extension43 having external clutch teeth 44 adapted to be engaged by the internalclutch teeth 45 carried within the axial extension 46 of the gear 39when the ear 39 is shifted to the left, as viewed in Figure 1. Suitablesynchronizing means, indicated generally at 41, is carried upon theaxial extension 45 of the gear 39, and cooperates with the frictionsurface 48 carried adjacent the periphery of the gear 32 in the mannerdescribed in the copending application of Robert Lapsley, Serial No.319,661, filed February 19, 1940, and it is not believed that anydetailed description thereof is necessary herein.

The gear 32, as shown more in detail in Figure 2, is provided withcircumferentially spaced ports or passageways 50 which have their axesslightly offset relative to the radial planes defined by the lines A, Band C, the angular displacement between the axes of the passageways 50and the radial lines passing through the center of the outer ends 52 ofthese passageways being approximately although this may be varied,depending upon the gear ratios in the transmission which control thespeed of rotation of the gear 32. It should also be noted that thepassageways 50 are inclined in an axial direction, the outer ends 52thereof opening into bosses 53 formed in the lateral face of the gear32, while the inner ends thereof, indicated at 54, open into theinternal angular surface of the hub 33 substantially at the axial centerthereof.

Due to this angular inclination of the passageways 50, it will beapparent that the ends 52 of these passageways open out at a radialdistance equivalent to the point of meshing engagement of the teeth 24and 25 of the gears 29 and 26. Since these teeth are in constant meshingengagement, the operation of the transmission will result in thedischarge laterally from the point of meshing engagement of these teethin an axial direction toward the outer end 52 of the passageways 50 asthey rotate by this point. This causes the defining edges of the ports52 to be angled or cocked to lie in the plane of the inclined bosssurface 53, the trailing side of this defining'edge, indicated at 5|,projecting further outwardly toward the point of meshing engagement thanthe leading side of this edge, considered with respect to the directionof rotation of the gear 32, as indicated by the arrow in Figure 2. Sincethe lubricant discharged from the meshing gears 20 and 26 is directedboth laterally and also tangentially in the direction of approaches theangle of cooking of the passageways 53. This, in effect, provides forreceiving the oil thrown off from gears 20 and 25 and directing this oilat considerable velocity into the passageway without too rapid a changein its direction of movement, due to the angular offset of thepassageway. The bosses 53 formed in the lateral face of the gear 32bring the ports 52 closely adjacent the point of meshing engagementwhereby the full value of this scooping action can be realized. As aresult, a certain proportion of this lubricant discharge is forced intocontact with the annular surfaces of the bearings 34 and provides a thinfilm of lubricant sufiicient for adequate lubrication of the bearings.

It is therefore believed apparent that I have provided a novel means forinsuring lubrication of a rotatably journalled gear which is so isolatedas to render other lubricating means undesirable, and the constructionalso provides for controlled amounts of lubricant being passed to thebearings of this journalled gear.

I am aware that various changes may be made in certain details of thepresent construction, and I therefore do not intend to be limited exceptas defined by the scope and spirit of the appended claims.

I claim:

1. In combination, in a transmission gear having a hub portionjournalled on antifriction bearings, a plurality of circumferentiallyspaced. bosses formed on one lateral face of the ear, ports in saidbosses, pockets in said bosses opening into said ports, and passagewaysextending laterally and radially inwardly from said bosses and openinginto the hub of said gear.

2. The combination of claim 1 wherein the axes of said passagewaysextend at a slight angle to transverse radial planes through the axes ofsaid ports.

3. In a gear having a hub adapted to be journalled on antifrictionroller bearings, a plurality of circumferentially spaced bosses formedon one lateral face of said gear, a plurality of passageways extendingfrom the hub of said gear laterally and radially outwardly toward saidbosses and terminating in ports in said bosses, said passageways havingtheir axes arranged so that one side of the defining edge of the portopening at each boss acts as a lubricant receiving pocket upon rotationof said gear in one direction.

4. In combination, in a transmission, a pair of parallel shafts, a pairof constantly meshing gears on said shafts, a third gear having a hub,bearing means in said hub rotatably journalling said third gear on oneof said shafts immediately adjacent one of said pair of gears, saidthird gear being of a larger diameter than said adjacent one of said setof gears, and circumferentially spaced port means in the adjacentlateral face of said third gear adapted to rotate past the point ofmeshing engagement of said pair of gears and including radially andaxially inwardly extending passageways to the hub thereof for receivinglubricant thrown laterally from said point and directing it into thebearing means of said third gear.

5. The combination of claim 4 wherein said circumferentially spacedmeans includes bosses projecting from the lateral face of said thirdgear to bring the inlet end of said passageways into close proximity tosaid point of meshing engagement. rotation, the resultant direction ofthis lubricant 6. The combination of claim 4 further characterized inthat the axes of said passageways are cocked slightly relative to radiiof said third gear and the inlet ends thereof have defining edgesproviding a lubricant receiving pocket.

7. In combination, in a transmission having a pair of parallel shafts, aset of constantly meshing gears on said shafts, a third gear rotatablyjournalled on one of said shafts immediately adjacent one of said set ofgears and of a larger diameter, said third gear at all times rotatingslower than said adjacent one of said set of gears, circumferentiallyspaced bosses formed in the lateral face of said third gear having portstherein disposed at a radius equal to the pitch radius of said adjacentgear of said set of gears,

said third gear having passageways leading radii ally and axiallyinwardly from said ports to the I

